Benzoic acid and water

The chemical species present initially are benzoic acid and water, Cg H5 CO2 H and H2 O. The H3 mentioned in the problem is formed as the solution comes to equilibrium. 

Initially, benzoic acid and water are the only species present. 

Whilst the various types of physical mixture have been dealt with above, from complete immiscibility to complete miscibility, two special cases may now be taken, the first of which is that of benzoic acid and water. Here we are essentially concerned with the fact that in the same pair of bodies, immiscibility may be gradually transformed into simple, then mutual solubility, and finally into complete miscibility. In the previous cases the transformation is effected by rise of temperature below the cryohydric temperature ice and benzoic acid are practically without action on one another on fusion of the ice, one-sided solution of the benzoic acid begins later, on fusion of the acid, mutual solubility occurs, changing eventually to complete miscibility. AlexejefTs investigations on this point have settled that benzoic acid, after an increase of solubility with rise of temperature has shown itself, melts at 90°, i.e. 31-4° under the usual melting point This is, therefore,... 

To the right of eabcdf, homogeneoUvS liciuid niixiuiH of benzoic acid and water. 

Solubility of Mixtures of Liquid Benzoic Acid and Water. 

Poly(A -isopropylacrylamide) acetonitrile and water benzoic acid and water 2004PAN 2009HOF... 

Aluminum complex greases, obtained by the reaction of aluminum isopropylate with a mixture of benzoic acid and fatty acids. These greases have a remarkable resistance to water, very good adhesion to metallic surfaces, good mechanical stability properties and resistance to temperature. They are less common than the first two types. 

B) Benzoyl derivatives. Most amino-acids can be benzoyl-ated when their solutions in 10% aqueous sodium hydroxide are shaken with a small excess of benzoyl chloride until a clear solution is obtained (Schotten-Baumann reaction, p. 243). Acidification of the solution then precipitates the benzoyl derivative and the excess of benzoic acid, and the mixture must be filtered off, washed with water, and recrystallised (usually from ethanol) to obtain the pure derivative. (M.ps., p. 555 )... 

Method 2. This preparation should be carried out in the fume cupboard since nitrous fumes are evolved. Place 62 g. of benzoic acid and 300 ml. of concentrated sulphuric acid in a 2-litre roimd-bottomed flask, warm on a water bath with shaldng until the benzoic acid dissolves, and cool to 20°. Add 100 ml. of fuming nitric acid (sp. gr. 1-54) in portions... 

Propiophenone. Propiophenone [93-55-0] (ethyl phenyl ketone) is a colorless Hquid with a flowery odor. It can be prepared by the Friedel-Crafts reaction of benzene and propionyl chloride in the presence of aluminum chloride (346), or by the catalytic reaction of benzoic acid and propionic acid in the presence of water (347). Propiophenone is commercially available (348), and is sold in Japan at 2700 Y/kg (349). It is used in the production of ephedrine, as a fragrance enhancer, and as a polymerization sensitizer. 

Henkel Rearrangement of Benzoic Acid and Phthalic Anhydride. Henkel technology is based on the conversion of benzenecarboxyhc acids to their potassium salts. The salts are rearranged in the presence of carbon dioxide and a catalyst such as cadmium or zinc oxide to form dipotassium terephthalate, which is converted to terephthahc acid (59—61). Henkel technology is obsolete and is no longer practiced, but it was once commercialized by Teijin Hercules Chemical Co. and Kawasaki Kasei Chemicals Ltd. Both processes foUowed a route starting with oxidation of napthalene to phthahc anhydride. In the Teijin process, the phthaHc anhydride was converted sequentially to monopotassium and then dipotassium o-phthalate by aqueous recycle of monopotassium and dipotassium terephthalate (62). The dipotassium o-phthalate was recovered and isomerized in carbon dioxide at a pressure of 1000—5000 kPa ( 10 50 atm) and at 350—450°C. The product dipotassium terephthalate was dissolved in water and recycled as noted above. Production of monopotassium o-phthalate released terephthahc acid, which was filtered, dried, and stored (63,64). 

Ben /ben ate [120-51-4] CgH COOCH2CgH, mp, 21°C, cff , 1.118 bp, 323—324°C at 101.3 kPa , 1.5681. This is a colorless, oily liquid with a faiat, pleasant aromatic odor and a sharp, burning taste. It occurs naturally iu Pern and Tolu balsams, is spariugly volatile with steam, and is iusoluble iu water. Benzyl benzoate is prepared commercially by the direct esterification of benzoic acid and benzyl alcohol or by reaction of benzyl chloride and sodium benzoate. The pleasant odor of benzyl benzoate, like other benzoic esters, has long been utilized iu the perfume iadustry, where it is employed as a solvent for synthetic musks and as a fixative. It has also been used iu confectionery and chewing gum flavors. 

The influence of NH., and CO, on the chromatographic behaviour of benzoic acid and its derivatives (o-, m-, p-hydroxybenzoic, nitrobenzoic, aminobenzoic, chlorobenzoic acids) was studied. The work was carried out by means of upgoing TLC on Sorbfil plates. Isopropanol- and ethyl acetate-containing water-organic eluents were used as mobile phases in the absence or presence of gaseous modifiers in the MP. The novel modification of TLC has been found to separate benzoic acids with different values of their dissociation constants more effectively than water-organic mobile phases. 

When heated with mineral acids Z-cocaine is hydrolysed into Z-ecgonine (p. 96), benzoic acid and methyl alcohol and a like change takes place with baryta water. If the alkaloid is boiled with water, methyl alcohol is split off and a new base, benzoyl-Z-ecgonine is formed, which in turn can be hydrolysed by acids or alkalis into Z-ecgoninc and benzoic acid. Cocaine is, therefore, methylbenzoyl-Z-ecgonine. 

Tropacocaine (Benzoyl-ili-tropeine), CuHj gOgN, was discovered by Giesel in Java coca leaves and has since been found in Peruvian coca. Its preparation from the former source has been described by Hara and Sakamoto, It crystallises in needles, m.p. 49°, is insoluble in water, but soluble in alcohol, ether or dilute ammonia and is generally prepared by benzoylating /t-tropine, and purified as the hydrochloride. Its alcoholic solution is alkaline and optically inactive. The hydrochloride forms needles, m.p. 271° (dec.), and the hydrobromide leaflets. The aurichloride separates in minute yellow needles, m.p. 208°, from hot aqueous solutions the picrate has m.p. 238-9°. When heated with hydrochloric acid or baryta water the alkaloid is hydrolysed to benzoic acid and -tropine. ... 

Aconitine contains four methoxyl groups and three hydroxyl groups (triacetyl derivative, m.p. 207-8°). On hydrolysis by water under pressure, or by boiling with dilute acid, it loses 1 mol. of acetic acid and forms benzoylaconine, whilst hydrolysis by alkalis eliminates both acetic and benzoic acids and yields aconine. 

A perbenzoic acid solution in benzene is prepared as in Chapter 17, Section II. (This solution is approximately 1.8 A/ in perbenzoic acid.) To 67 ml (approx. 0.12 mole of perbenzoic acid) of this solution contained in an Erlenmeyer flask is added 0.10 mole of the ketone in one batch. The resulting solution is swirled at intervals and allowed to stand at room temperature for 10 days. The solution is then washed three times with 50-ml portions of saturated sodium bicarbonate solution to remove benzoic acid and unreacted peracid, and is then washed with water. The solution is dried (anhydrous sodium sulfate), the benzene is evaporated, and the residue is fractionally distilled at reduced pressure to give the ester. 

The ionization of benzoic acids in water at 25° was used by Hammett as the standard reaction for the original qp treatment (2a). This reaction and several analogous reactions, e.g., ionization and ester saponification rates of benzoic acids, cinnamic acids, and phenylpropiolic acids, gives ap correlations of relatively high precision. Taft and Lewis classified such reactions in an A category (2f). Reexamination of these A reactions, as well as additional analogous data which have become available subsequently, provided eight reaction series of data of apparently comparable reliability. In the para position, each of these sets of data meets the necessary condition of a minimal basis set... 

A ruthenium porphyrin hydride complex was lirst prepared by protonation of the dianion, [Ru(TTP) in THF using benzoic acid or water as the proton source. The diamagnetic complex, formulated as the anionic Ru(If) hydride Ru(TTP)(H )(THF)l , showed by H NMR spectroscopy that the two faces of the porphyrin were not equivalent, and the hydride resonance appeared dramatically shifted upheld to —57.04 ppm. The hydride ligand in the osmium analogue resonates at —66.06 ppm. Reaction of [Ru(TTP)(H)(THF)j with excess benzoic-acid led to loss of the hydride ligand and formation of Ru(TTP)(THF)2. 

Since dosage forms contain more than just active drug, it is of practical interest to understand how the various components from a multicomponent solid influence their own dissolution and release. Nelson [18] was one of the first pharma-ceuticists to ponder this question and perform the initial dissolution studies. Unfortunately, Nelson initially considered the dissolution of interacting solids (benzoic acid + trisodium phosphate), which is a more complicated and more complex situation than simple multicomponent dissolution of noninteracting solids. Nelson did show that for his benzoic acid and trisodium phosphate pellets, there was a maximum increase in benzoic acid dissolution in water at a mole fraction ratio of 2 1 (benzoic acid trisodium phosphate) and that the benzoic acid dissolution rate associated with the maximum rate was some 40 times greater than that of benzoic acid alone. 

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